BIGAL
I had read all that good stuff about the HERESYs too, but we were super disappointed with the HERESY IIIs.
We were ready to pay big for them thinking they would be an end-game speaker for us... and kill the little RP-160Ms. Nope!
Truthfully, we could not have lived with the HERESYs. The RP-160Ms slaughtered them in every department!
Interestingly, with an RP-160M on one channel and a HERESY on the other, we could discern no difference in sensitivity/efficiency - and that was being driven by our FIRST WATT J2... (No slouch!) This was very curious because the HERESYs are supposedly higher in sensitivity (99dB) and higher in Nominal Impedance (8-Ohm) than the RP-160ms (95dB/4-Ohm) - factors which suits the Single Ended FIRST WATT J2 and should have given the HERESYs a useful advantage. Nope!
In short, either the HERESYs are badly overrated - or the RP-160Ms are badly under-rated in these respects. We believe a good chunk of both.
I'm sure the FORTEs and the CORNWALLs are in a whole other league over and above the HERESYs. Have to admit, we've never heard either.
On to the LEBEN PHONO and the AUD23 SUT. We love them. That said, they suit our LO MC SHELTER 501 II cartridge - and our sonic taste preferences.
Phonos, SUTs and Cartridges are very match dependent and taste-dependent. So, I guess you'd have to suck it and see with your Micro Benz Ace.

Wow, really interesting. Thanks for your input. I've heard so much good stuff about the Heresy's so the RP-160M's must be impressive. I had the Cornwall iii's for a few weeks and they were phenomenal, but the Forte iii's had a bit more refinement. Horses for courses I suppose. But if there was ever a speaker to completely rock the party and give that sense of 'live', then the Cornwall would be hard to beat.
The Heresy and Cornwall's share the same mid and tweeter horns so have a slightly similar sound signature, but the Cornwall's 15" woofer is something else. Talk about moving a lot of air.
How do you find the Leben phono stage and Auditorium 23 SUT? They're also considerations.
Cheers

PS: Sorry, ever heard the FORTE, but we spent invested a day and AB-ed the RP-160M versus the HERESY III - at home in our system with everything else constant - and the former won by a country mile. No contest! -SONDEK